Pipe coupling



Dec. 14, 1948.

Filed Dec. 29, 1945 N mw Q i m Nm 3 7 2 91 N mm 2 8 u 8 O Q mm 8 mm mmmv u Q mw Q NNmN Qw 2 NN 3 8% Km ow a *N/ Ofi Q Q X6 N @m m 6Q. 3

Jrwwxcr Mum I-LJ. Baock Patented Dec. 14, 1948 PIPE COUPLING WilliamHudson James Brock, Leamington Spa, England Application December 29,1945, Serial No. 637,882 In Great Britain January 2, 1945 3 Claims.

This invention relates to pipe couplings and it hasfor its object toprovide an improved form of coupling of the kind (hereinafter mentionedas the kind referred to) comprising a pair of easily separable couplingparts, each of which incorporates a valve arranged to close the exposedfluid opening of the coupling part when the latter is uncoupled and toopen automatically as the coupling parts are connected together, thusproviding a free fluid passage through the united coupling.

In particular it is the object of the invention to provide a coupling inwhich rubber or like resilient sealing means are provided for the valvesof the coupling parts to ensure a fluidtight seal in each of the twoparts when the latter are separated. In a pipe coupling of the kindreferred to, consisting of two coupling parts of which the firstcomprises a tubular stem with lateral apertures closed by a sleevesliding on the stem, and the second comprises a tubular body with an endaperture closed by an axially movable valve, the axially movable valvebeing displaced inwardly by the stem, and the sleeve being displacedalong the stem by the tubular body as the parts are brought together,until the apertures in the stem pass through the end aperture in thetubular body, according to the invention the sleeve and axially movablevalve are grooved circumferentially to receive sealing rings engagingrespectively with the stem and the curved wall of the end aperture inthe tubular body when the coupling parts are separated.

At least one of the sealing rings is preferably arranged to have freedomfor limited axial movement with respect to the part in which it ismounted, so that its position is dependent on the sense of the pressurediiference across it. Thus if desired the said sealing ring may be ofrectangular cross section, said ring being disposed within a groove oftrapezoidal shape in cross section. The sealing ring of the axiallymovable valve may be mounted within it. groove so that its outer part atleast has freedom to move axially.

Conveniently the sleeve member is formed at its inner end with a portionof reduced diameter which is slidable upon a corresponding reduceddiameter portion of the stem and which is grooved for the reception ofthe sealing ring belonging to the sleeve. An annular space between thereduced diameter portion of the tubular stem and the interior of thesleeve can be placed in permanent communication with the interior of thestem by one or more holes formed therein adjacent the outer end of thereduced diameter portion. Also the body of the first coupling partpreferably has an internal flange which engages t e tubular stem 50 asto impart thrust to said stem as the coupling is tightened. A tubularspigot on the sleeve may engage a sealing ring disposed within anannular groove in the inner end of the tubular body to produce afluidtight seal between the coupling parts.

The invention is illustrated by way of example in the accompanyingdrawings, in which:

Figure 1 is a sectional elevation of the coupling parts separated, thevalves being closed;

Figure 2 is a similar view showing the coupling fully united; and

Figure 3 is a fragmentary sectional view showing the position of theparts at a stage in the disconnection of the coupling.

In the following description, the ends of the two coupling parts whichengage each other when the parts are brought together are referred to asthe inner ends, and the other ends as the outer" ends.

The first part of the coupling is indicated at I 0 and comprises atubular body I I having an internal flange 12 at its outer end, theflange l2 being engaged at its inner side by a flange l3 on a tubularstem H which is thus located concentrically within the body H, andprojects through the outer end thereof as shown at I5, this projectingend being threaded at l6 for attachment to a pipe or other conduit (notshown). The inner end of the stem l4 has its external diameter reducedto form a spigot H, a passage [8 extending axially through the stem fromits outer end, being arranged to stop short of the flat inner end IQ ofthe stem N. The passage 18 however communicates with a circumferentialseries of ports 20 set back a little distance from this end I9. Ashallow circumferential groove 2| of V-shape in section is formed aroundthe stem I4, and the outer ends of the ports 20 lead into said groove.Within the body H and slidable on the stem H. is a sleeve 22 having anexternal flange 23 near its inner end, the sleeve 22 being urged towardsthe inner end of the body II by a spring 24 arranged between the saidflange 23 and the flange l3 on the stem, and being limited in itsoutward movement by a stop ring 25 screwed into the inner end of thebody I l to engage the sleeve flange 23. The internal diameter of thesleeve is stepped, its inner end part 26 fitting on the spigot ll of thestem. and the major portion of its length being of a diameter to fltslidably upon the larger main part of the stem I. When the sleeve flange23 is in engagement with the stop ring 25, the end part 26 surrounds theinner end of the stem I4 beyond the ports 20 therein, so that the ports20 open inio an annular space 21 between the stem spigo't ll and thesleeve 22. A sealing ring 28 is located in an internal circumferentialgroove around the smaller diameter part 26 of the sleeve, and a secondsealing ring 29 in a groove in the outer surface of the larger diameterpart of the stem engages the interior of the larger diameter part of thesleeve 22. A series of small radial ports 30 in the stem I4 close to thechange in diameter of the latter connect the annular space 21permanently to the bore I8 of the stem I4. The end face of the sleevewhich is exposed at the inner end of the coupling part carries acylindrical flange 3|, the internal diameter of the flange being largerthan the diameter of the stem I4, and the end face of the flange 3Ibeing chamfered t provide a narrow face at its radially inner edge. Thebody II is threaded externally at 32, and is preferably formed with ahexagonal flange 33 to enable it to be gripped by a spanner.

The second part of the coupling is indicated generally at Illa andcomprises a tubular body 34 having a uniform internal diameter except atits inner end, where it has a short portion 35 of reduced diameterproviding an end aperture smaller than the main bore of the body. On theouter end is mounted an adaptor 36 having a boss 31 for attachment to apipe or hose (not shown), the adaptor 36 being secured by an externalthread 38 on the body. In the body 34 there is axially slidable a valvemember 39 having a head portion 40 adapted to flt closely in the reducedportion 35 of the body, and a convergent tail portion from which projectlateral wings 4I adapted to guide the valve member in the body 34. Thevalve member 39 is urged by a spring 42 towards a position in which itshead 40 lies in the reduced portion 35 of the body, the wings 4I thenengaging the shoulder 43 at the change of diameter in the body. Thevalve member 39 has a circumferential groove 44 in its head portion toreceive a sealing ring 45 which engages the curved wall of the reducedportion 35 of the body 34 to seal the coupling part I011. The groove 44is of trapezoidal shape in radial section, the side of the groove 44nearer the tail 4| of the valve member being inclined so that the grooveis of increasing width towards its mouth, thus allowing the radiallyouter part of the ring to move axially to a greater extent than theinner part. The sealing ring 45 is composed of soft rubber or likematerial, and can therefore readily alter its shape to accommodate suchmovements. A tube nut 46 is mounted on the part Illa of the coupling,its internal flange 41 being located between a flange 48 on the body,and the adaptor.

In each of the coupling parts III and Illa, when the valve therein is inits closed position, the central member, i. e. the stem I4 in the firstpart III and the valve member 39 in the second part I M is flush with,or slightly proud of the immediately surrounding surface, so that thesecentral members I4, 39, which both have flat ends, make contact witheach other as soon as the parts are brought together, and simultaneouslywith, or slightly before, the engagement of the cylindrical flange 3| onthe sleeve 22 of the first part III with a sealing ring 49 set in anannular groove in the end face of the body 34 of the second couplingpart Illa. The head of the valve member 39 in the second coupling partIda has the same diameter as the inner end of the stem I4 01. the firstcoupling part I0, and the internal diameter 4 of the reduced end part 35of the body 34 of the second coupling part Illa is the same as theinternal diameter of the smaller end 28 of the sleeve 22.

When the coupling parts I0, Illa are separated, the valves in both areclosed, and escape of fluid from both is prevented, the sealing rings28, 45, which are of rubber or similar soft resilient ma terial,providing a substantially complete seal against leakage. When the partsIII, Illa are brought together, the end I9 of the stem I4 engages withthe head 40 of the valve 39 in the second part IOa, and the inner end ofthe body 34 of the second part Illa engages with the end of the sleeve22, with the result that the valve member 39 is pushed back into thebody, and the sleeve 22 is pushed along the stem I4. As this movementcontinues, the ports 20 in the stem I4 pass through the reduced endportion 35 of the body 34 into the larger diameter part thereof, thusproducing a fluid passage through the coupling, as will be seen inFigure 2, which shows the coupling parts fully tightened. Leakagebetween the parts when coupled together is prevented by the end seal 3I,49 between the sleeve and the body 34 and the parts may be so arrangedthat in the fully coupled condition the sleeve 22 is clamped tightlybetween the flange I3 on the stem I4 and the body 34 of the othercoupling part Illa as shown in Figure 2.

With the arrangement described, a coupling is provided in which sealingrings of rubber or like material can be employed to give an effectiveseal when the parts I0, I90. are separated, but cannot be damaged ordisplaced during coupling and uncoupling of the parts. It has beenfoundthat a sealing ring of the kind employed in this coupling is likelyto be displaced or damaged during movement over a port or controllingedge only if one side of the ring passes over the leading edge of theport, or the controlling edge, whilst there is a pressure differenceacross the seal with the higher pressure on the side remote from theport or edge. In such a case, the part of the seal which has passed overthe leading edge of the port, or the controlling edge, is liable to beforced out of the groove, and deformed or damaged. The improved couplingdevice is designed to ensure that if there is difference between thepressures of fluid in the two halves when they are coupled together,regardless of which half contains fluid at the higher pressure, the sealin that half will continue to prevent flow of fluid as the parts arecoupled, until the seal in the other half is in a position to allow acompletely free flow of fluid past it.

This action is shown in Figure 3, where the coupling parts I0, Illa arebeing separated, there being a superior fluid pressure in the couplingpart Illa when free flow through the coupling is interrupted. Relativeto the body 34 and sleeve 22, the valve member 39 and stem I4 aretogther moving towards the right as the nut 46 is unscrewed, so thatgroove 2I passes across the sealing ring, and at the same time thesealing ring 45 has to pass across the edge of the reduced diameterportion 35. By making the groove 44 of trapezoidal cross section, thesealing ring 45 can be displaced towards the left by any pressure fluidwhich may at first flow from the parts 24, along the outside of the stemI4. This prevents the sealing ring 45 from becoming pinched between theleft-hand edge of the groove 44 and the edge of the reduced diameterportion 35, until the danger of pinching is removed, namely when a pointin the disconnecting is reached at which the ports 20 are completelybeyond the sealing ringfl so as to prevent further leakage of pressurefluid.

Again, if the coupling parts are brought together with an excess ofpressure in the first half l0, the sealing ring 28 in the sleeve 22 doesnot pass fully over the leading edges of the ports 20 in the stem I4until the groove 44 in the valve member 39 in the other half l0a haspassed the controlling edge in that half to such an extent that theseal, by moving over against the side of the groove nearer to the tail4| of the valve member, leaves a clear passage for fluid between itselfand the controlling edge. If the excess of pressure is in the secondhalf I0a of the coupling, the sealing ring 45 in the valve member 39 isheld by the pressure against the side of the groove nearer to the head40 of the valve, and the sealing ring 45 does not wholly pass thecontrolling edge until the sealing ring 29 in the sleeve 22 hascompletely crossed the leading edge of the groove 2| in the stem [4 intowhich the ports open. On separating the coupling halves l0, No, if apressure difference is established as soon as th through passage isinterrupted, it is the sealing ring in the coupling part in which thepressure is the higher which first comes into action.

Owing to the fact that the flat faces of the central coupling partsengage as soon as the parts are brought together, no air can be includedwhen the parts are coupled, and, as the seal between the two parts ismade before the valves begin to open, no fluid can escape during eithercoupling or uncoupling.

What I claim is:

1. A pipe coupling of the kind referred to, consisting of two couplingparts of which the first comprises a i cgosed by a sleeve slidin or gwith t e a er an annular fluid space in permanent connection with theinterior of said stem, and the second comprises a tubular body with anend aperture closed by an axially movable valve, the axially movablevalve being displaced, inwardly by the stem, and the sleeve beingdisplaced along the stem by the tubular body as the parts are broughttogether, until the apertures in the stem pass through the end aperturein the tubular body, characterized by the fact that the sleeve andaxially movable valve are both grooved circumferentially and are fittedwith sealing rings engaging respectively with the end of the stem remotefrom said fluid port means and the curved wall of the end aperture inthe tubular body when the coupling parts are separated and that the stemis also grooved circumferentially and fitted with a sealing ring forengaging the end of the sleeve adjacent said fluid port means, wherebysaid annular space is sealed at each end thereof.

2. A pipe coupling as claimed in claim 1, wherein the sleeve member isformed at its inner end with a portion of reduced diameter, whichportion is slidable upon a corresponding reduced diameter portion of thestem and which is grooved for the reception of the sealing ringbelonging to the sleeve.

3. A pipe coupling as claimed in claim 1, wherein the sleeve member isformed at its inner end with a portion of reduced diameter, whichportion is slidable upon a corresponding reduced diameter portion of thestem and which is grooved for the reception of the sealing ringbelonging to the sleeve, and said annular space is formed between thereduced diameter portion of the tubular stem and the interior of thesleeve and is placed in permanent communication with the interior of thestem by one or more holes formed therein adjacent the outer end of thereduced diameter portion.

WILLIAM HUDSON JAMES BROCK.

REFERENCES CITED The following references are of record in the file orthis patent:

UNITED STATES PATENTS Number Name Date 1,335,521 Murphy Mar. 30, 19202,185,173 Fortune Jan. 2, 1940 2,208,286 Berger July 16, 1940 2,208,620Baisch July 23, 1940 2,210,282 Corbin Aug. 6, 1940 2,254,997 FisherSept. 2, 1941 2,314,683 Berry Mar. 23, 1943 2,360,733 Smith Oct. 7, 19442,383,249 Harwick Aug. 21, 1945 2,393,679 Gunderson Jan. 29, 1946

